I would like your recommendations for increasing the exposure latitude of Kodak and Ilford B&W 35mm film

I shoot 35mm roll film and cannot control the light on every subject I photograph.

With standard processing, the 400TX data sheet's Characteristic Curve seems to have an exposure latitude of +5 to -5 stops. However, with normal processing, I get much less detail at 400ISO when underexposing more than 1xstop. This conforms well with Kodak's May 2007 data sheet.

I am very unhappy with and not interested in pushing B&W film.

To me the concept of processing that roll in order to have the widest exposure latitude possible makes the most sense.
By exposure latitude I mean I want to maintain detail in the darker portions and lighter portions of any image on that roll, as far as possible.

I understand and have used the concept of overexposing (say +0.5 stops) and underdeveloping the negative. As far as I know, this is the accepted method to achieve the goal I have outlined. I understand that low contrast subjects may look flat when film is processed this way.

What I don't have is your experience. Please provide examples of Kodak or Ilford film, ISO speed used to meter, with developer, time and agitation method that have worked for you. I could also benefit if you provide the exposure latitude you achieved. I do not process at home now but have found a professional lab that can do custom work for me. I would prefer not to use "fine grain" developers like D76 and XTOL.

For example, dr5.com claims a +1/3rd stop to -3 stop Exposure Latitude for their B&W reversal process for HP5 Plus shot at 400ISO.

dfbldwn wrote:I would like your recommendations for increasing the exposure latitude of Kodak and Ilford B&W 35mm film

I shoot 35mm roll film and cannot control the light on every subject I photograph.

With standard processing, the 400TX data sheet's Characteristic Curve seems to have an exposure latitude of +5 to -5 stops. However, with normal processing, I get much less detail at 400ISO when underexposing more than 1xstop. This conforms well with Kodak's May 2007 data sheet.

I am very unhappy with and not interested in pushing B&W film.

To me the concept of processing that roll in order to have the widest exposure latitude possible makes the most sense.
By exposure latitude I mean I want to maintain detail in the darker portions and lighter portions of any image on that roll, as far as possible.

I understand and have used the concept of overexposing (say +0.5 stops) and underdeveloping the negative. As far as I know, this is the accepted method to achieve the goal I have outlined. I understand that low contrast subjects may look flat when film is processed this way.

What I don't have is your experience. Please provide examples of Kodak or Ilford film, ISO speed used to meter, with developer, time and agitation method that have worked for you. I could also benefit if you provide the exposure latitude you achieved. I do not process at home now but have found a professional lab that can do custom work for me. I would prefer not to use "fine grain" developers like D76 and XTOL.

For example, dr5.com claims a +1/3rd stop to -3 stop Exposure Latitude for their B&W reversal process for HP5 Plus shot at 400ISO.

Cheers,
David

You cannot really increase the latitude of film. You can maximize the latitude that is there, however, by using compensating development. By using a Metol-based developer such as D-76 diluted 1:1 or 1:2, you can avoid blocked-up highlights. All latitude is for over-exposure. There is no under-exposure latitude at all. Gentle agitation (2 inversions per minute) should work well. Use 75% of the recommended times. Do not use Rodinal, no matter what you hear from others!

The dilution is important. Do not use full-strength developer. Metol's activity is suppressed by the release of acidic by-products during development. If no agitation is used, these by-products (which are heavier than the developer solution) tend to slide down the film surface and cause streaking. This is why agitation is important. But agitation should be gentle! Just 2 inversions, once per minute.

Ornello wrote:All latitude is for over-exposure. There is no under-exposure latitude at all.

This makes much sense. I never suspected. The rest of your reply explains very well what it takes to accomplish this .

Ornello wrote:Do not use Rodinal

Got it! The very word will never pass my lips.

Could HC-110 ever be diluted enough to provide compensating development comparable to D76?
I know there's no substitute to D76 but HC-110 could be much more convenient.

I suggest strongly using a Metol-based developer such as D-76 or ID-11. Most other developers use phenidone or related compounds as developing agents, and these are not as sensitive to the release of bromide from the emulsion surface. In other words, Metol-based developers are best for the purpose of controlling highlights. I believe HC-110 is among those 'other developers'. Dilution alone is not enough: you need bromide sensitivity, and Metol has that property.

Ornello wrote:I suggest strongly using a Metol-based developer such as D-76 or ID-11. Most other developers use phenidone or related compounds as developing agents, and these are not as sensitive to the release of bromide from the emulsion surface. In other words, Metol-based developers are best for the purpose of controlling highlights. I believe HC-110 is among those 'other developers'. Dilution alone is not enough: you need bromide sensitivity, and Metol has that property.

I can now understand what you already wrote in your first reply. Thank you for your patience and generosity.

Ornello wrote:I suggest strongly using a Metol-based developer such as D-76 or ID-11. Most other developers use phenidone or related compounds as developing agents, and these are not as sensitive to the release of bromide from the emulsion surface. In other words, Metol-based developers are best for the purpose of controlling highlights. I believe HC-110 is among those 'other developers'. Dilution alone is not enough: you need bromide sensitivity, and Metol has that property.

I can now understand what you already wrote in your first reply. Thank you for your patience and generosity.

You can buy the raw ingredients from Photographer's Formulary and make your own developers. The formula known as D23 (an old Kodak formula) would be ideal for what you are trying to do. It contains no accelerant (alkali). I would dilute it 1:1 and start there.

7.5grams of Metol
100 grams of Sodium Sulfite
All for 1 litre of stock developer.

I asked for help and you have been generous with your time. I'll certainly be taking your advice, even if it involves using a "fine grain" developer. I ask these questions to better understand what is going on. It's not your fault this kind of information isn't in the data sheets, but you sure have filled some big gaps.
Cheers,
David

I asked for help and you have been generous with your time. I'll certainly be taking your advice, even if it involves using a "fine grain" developer. I ask these questions to better understand what is going on. It's not your fault this kind of information isn't in the data sheets, but you sure have filled some big gaps.
Cheers,
David

I would suggest you use D23 at half strength, as it's easy to make. Otherwise, buy D76 and use it at half strength. Trust me on this. The hydroquinone (HQ) in D76 is there mostly for preservative purposes. It does not contribute much to the development process at all. D76 without the HQ is basically what D23 is. D23 does not keep well, it must be mixed shortly before use. Use at half-strength and discard after use.

"D-23 is an ideal developer for mixing because it is a simple two-ingredient formula that is relatively cheap and versatile- -since it doesn't come in premixed form there is no other way to obtain it than by mixing your own. D-23 contains 7.5 grams of metol developing agent and 100 grams of sodium sulfite preservative. The sulfite provides sufficient alkalinity to activate and maintain the developing process, and in addition acts as a solvent. The solvent action is two-fold. First, sulfite partially dissolves exposed silver halide grains, allowing the developing agent to get at internal latent image specks where development must begin, allowing complete development of exposed halides and reducing speed loss. Secondly, when the sulfite dissolves exposed or unexposed silver halides it frees up metallic silver which is then plated back onto partially -developed grains in the emulsion in a process known as physical development--this tends to blur the rough outlines of the silver, giving a soft, semi-fine-grain effect.

Metol by itself is a soft-working, low-fog agent, and with the low alkalinity of the sodium sulfite plus its anti-oxidant qualities, D-23 is almost guaranteed not to block up high values even when long development times are required. This is the developer Ansel Adams chose for his "Moonrise, Hernandez, New Mexico" negative. He was concerned that the moon would come out overdeveloped and not show any detail. Later he said if he had known how dark the foreground area was he would have given the whole negative another stop of exposure. Adams couldn't find his exposure meter in his hurry to make the shot before the sun set behind him. He later used a silver-based intensifier to enhance the foreground of this famous negative. But under normal circumstances, where correct exposure is given, D-23 renders excellent shadow detail.

D-23 is sometimes used as a one-shot developer and then discarded. Kodak does however provide a replenisher formula, known as DK-25R, which allows the developer to be used for up to 26 rolls. One of the things that happens when the replenishment method is used is a buildup of silver in the developer solution. In the past, developers like D-23 were often replenished continuously, far beyond the recommended film capacity, and negatives were generally developed by inspection. When silver content builds up in D-23 its functionality is radically altered. Physical development takes place in direct proportion to the amount of silver developed out in the emulsion, causing an intensifying effect that is pronounced in the high values. Though unpredictable, this effect was sometimes exploited."

Maybe start with 8 minutes on HP5. That's just a guess. Use grade 3, not grade 2 to print on, and work back from there to adjust the development time. Take several test rolls of film on a clear sunny day. Bracket the exposures and make notes.

35mm negatives should have lower density in the highlights than large-format negatives, and have more shadow density. This means you should cut the speed rating by about 2/3 of a stop (give 2/3 stop more exposure). Rate ISO 400 film at 250 or so.

The average density may not be that much different, but the results will be superior this way. What kind of enlarger are you using?

Ornello wrote:Maybe start with 8 minutes on HP5. That's just a guess. Use grade 3, not grade 2 to print on, and work back from there to adjust the development time. 35mm negatives should have lower density in the highlights than large-format negatives, and have more shadow density. This means you should cut the speed rating by about 2/3 of a stop (give 2/3 stop more exposure).

I went ahead and looked it up on Massive Dev Chart: 13 minutes for both 400TX and HP5+. Some old guy on some website once said overexpose 1/2 stop so I'll meter at 400ISO and open aperture half a stop. Same old guy also said use 2/3rds recommended development time so I'll start with 13*2/3 = 8+2/3rds minute (520 seconds) and still use your 2 gentle inversions per minute, although I'm daunted that Kodak & Ilford & Massive Dev Chart all say continuous agitation for first minute so I'll probably consistently do more than 2 inversions the first minute.

Ornello wrote:What kind of enlarger are you using?

Gulp! IF I can find the time to shoot the film, buy the chemistry, develop and even more time to scan the roll and IF I stumble across a Time/Temperature/Concentation combo that scans well, then I'll think about an enlarger. I do know your thesis that the true test is how it looks on Grade 3 paper, rather than using a Densitometry. It is good judgment like that which keeps me coming back to this forum.

I prefer adjusting a scanned image's contrast to wetwork with an enlarger in a darkroom.

Ornello wrote:Maybe start with 8 minutes on HP5. That's just a guess. Use grade 3, not grade 2 to print on, and work back from there to adjust the development time. 35mm negatives should have lower density in the highlights than large-format negatives, and have more shadow density. This means you should cut the speed rating by about 2/3 of a stop (give 2/3 stop more exposure).

I went ahead and looked it up on Massive Dev Chart: 13 minutes for both 400TX and HP5+. Some old guy on some website once said overexpose 1/2 stop so I'll meter at 400ISO and open aperture half a stop. Same old guy also said use 2/3rds recommended development time so I'll start with 13*2/3 = 8+2/3rds minute (520 seconds) and still use your 2 gentle inversions per minute, although I'm daunted that Kodak & Ilford & Massive Dev Chart all say continuous agitation for first minute so I'll probably consistently do more than 2 inversions the first minute.

Ornello wrote:What kind of enlarger are you using?

Gulp! IF I can find the time to shoot the film, buy the chemistry, develop and even more time to scan the roll and IF I stumble across a Time/Temperature/Concentation combo that scans well, then I'll think about an enlarger. I do know your thesis that the true test is how it looks on Grade 3 paper, rather than using a Densitometry. It is good judgment like that which keeps me coming back to this forum.

I prefer adjusting a scanned image's contrast to wetwork with an enlarger in a darkroom.

Scanning is not the way to go. You don't want to do that. The negatives ideal for printing will not look good scanned, and vice versa. You need to enlarge these negatives in an enlarger, and work back from the results. Start with 8 minutes, don't start with 13 minutes. Expose about 2/3 stop more ISO 400 (use 250 on the meter). Trust me. I have done all of this before.

If you're going to scan, you can just use color negative film to start with, and get better results. B&W film is silver particles, and those show up as more pronounced grain when scanned than when printed. Trust me.

Use continuous agitation for the first 30 seconds or so, but use gentle inversions.

I haven't used it in a long time. It's exactly what you need though. This will be my last response. I thought you were going to print the negatives with an enlarger. If not, I have nothing more to say. Scanned B&W film will not give quality equal to printing no matter how you process it.

Ornello wrote:Scanning is not the way to go. You don't want to do that.

Got it. Scanning = bad, condensor enlarger with Grade 3 paper is best for final judgment of image.

Ornello wrote:B&W film is silver particles, and those show up as more pronounced grain when scanned

a quiet reservation: I see this in scans of B&W negatives most often when someone has been profligate with Unsharp Mask function and/or aggressive with Curves or other Contrast intervention making an originally underexposed negative worse.

Ornello wrote:The negatives ideal for printing will not look good scanned, and vice versa

I fully agree with this excellent and accurate observation. I know what negatives work with scanning, the only successful darkroom print I've ever made was contact sheets. I've personally seen a professional's success: All negatives were lost. He had the contact sheet scanned at high enough resolution and had each individual image enlarged and printed. The result pleased him.

Ornello wrote:If you're going to scan, you can just use color negative film to start with

I choke, I groan, I pause to recover lost ability to breathe. Color film, slide or negative, has nowhere near the Exposure Latitude of B&W film under-exposed at boxtop speed and over-developed at manufacturer's recommendation. Any attempt to change the Exposure Latitude of color film will leave one spending the rest of their natural life trying to fix the color shift. It is the opposite of my original post.

Full disclosure: Kodak Gold KGT (a.k.a. Ultramax, the 800 speed) gave me a full +/-6 stops Exposure Latitude for a season at one CVS. Your suggestion to use color film was brilliant in those circumstances. That CVS changed its processing and Kodak stopped making that film in 35mm cartridges. Game over.

pirateoversixty wrote:How does d-23 compare with your old favorites from Crawley?

Thanks, Jim..

Ornello wrote: It's [D-23]exactly what you need though

I think it's a good fit. Mix just before using and all the right development properties. Thanks again, Michael.